Skip to content
Skip to main content

OU on the BBC: Background Brief - How Bad Is Fat? The Story So Far

Updated Tuesday, 8th August 2006
There are known health issues associated with fat, but are all fats bad for you? Get the background brief

This page was published over 16 years ago. Please be aware that due to the passage of time, the information provided on this page may be out of date or otherwise inaccurate, and any views or opinions expressed may no longer be relevant. Some technical elements such as audio-visual and interactive media may no longer work. For more detail, see how we deal with older content.

Cooking oil


- Almost half of the UK’s population is currently overweight

- 1 in 5 people is clinically obese

- At any given time, around a third of us are trying to lose weight.

Over the last few decades, more and more links have been established between overweight and serious health conditions such as heart disease and late onset diabetes. And since being overweight also tends to bring people down psychologically, it’s not surprising fat is now generally perceived to be Public Enemy No 1.

But is it ?

Here in the 21st century we’ve almost lost sight of the fact that dietary fat is relatively rare in nature - and small amounts can be nutritionally valuable. Repeat: valuable!
In the Stone Age our ancestors never knew where their next square meal was coming from. That’s why we’ve evolved to LOVE the taste of fatty foods – and our bodies are all too expert at storing it away for us. Nature made us love cheesy dips and chocolate biscuits ...

Polar Bear Most people are all too familiar with that lovely blanket of fat that lurks beneath the skin like particularly resilient carpet underlay…. This type of fat increases and decreases in direct proportion to how much food we’re eating versus how much activity we do. But there’s another type of fat too, that lies between our muscles, around the lymph nodes, and polar bears revealed what that’s all about...

Polar Bear and Scientists Scientists decided to look at polar bears because their lifestyle involves a long period of starvation through the winter. They go into their snowholes at the beginning of winter, well-fed and looking like chubby butterballs, and they emerge several months later as skinny as supermodels. But what the reserarchers found is that the fat around their lymph nodes never diminishes, no matter how skinny they become. Further investigation showed that this kind of fat isn’t there to provide energy at all – it’s there to help the body fight disease.

Fat between muscles BODY FAT IS GOOD - SHOCKER!!
So this type of fat is distinctly good news for the body. Not just for polar bears but for all of us. So this is one reason why you should never give up eating fat …But there are many sorts of fat in the diet – and some fats are better than others …

All fat is made out of the chemicals carbon, oxygen and hydrogen. These simple molecules can be assembled in different ways – resulting in different types of fat, with very different properties. Work is going on to find out more about them all, but there are some basic divisions all nutritionists would agree on.

Croissants SATURATED FAT: this sort of fat is usually characterised by being solid at room temperature. And it tends to come from an animal source – meat or dairy. The standard advice is to cut right down on this type of fat. Ok it tastes great, but nutritionally it does nothing for us – our bodies are quite capable of making their own saturated fats. And this type of fat is a big factor in some life-shortening conditions too.

Avocados UNSATURATED FATS. These are the good guys. They tend to come from vegetable products, and our bodies need these substances. There are two main types of unsaturated fat: polyunsaturated and mono-unsaturated.

Mono-unsaturated are the best because they are linked with "good" blood cholesterol. Avocados and olives are particularly good sources.

We only need small amounts of any fat though … a little goes a very long way. And as we’ve already mentioned, your body will store all excess for a rainy day. Right where you probably feel you least need it!

Bet you’ve never seen a fat fish? It must be all that swimming they do… But seriously, certain fish such as mackerel, salmon and tuna contain so-called ‘fish oils’. These are much talked about at the moment, because they seem to be very beneficial. Fish oils contain a particular kind of polyunsaturated fat that is rare elsewhere. It’s hard to say whether these oils are "essential" because the earliest humans probably never ate a fish in their lives … but dieticians now recommend we include them in the diet. If you don’t eat fish, some experts suggest you take linseed oil capsules instead which do a similar job.

First broadcast: Friday 15 Oct 1999 on BBC TWO


Become an OU student


Ratings & Comments

Share this free course

Copyright information

Skip Rate and Review

For further information, take a look at our frequently asked questions which may give you the support you need.

Have a question?